Thread cutter for knitting machines



Nov. 2, 1926. 1,605,846

I 0.. KOENIG THREAD CUTTER FOR KNITTING MACHINES Filed Jan. 1a, 1926 [NI ENTER 77727 KDEMG' 1 B 1 V ATTK Patented Nov. 2, 1926.

UNITED STATES PATENT OFFICE. l

OTTO KOENIG, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR OF ONE-FIFTH TO ALFRED FAISST, OF SAN FRANCISCO, CALIFORNIA.

THREAD CUTTER FOR KNITTING MACHINES.

Application filed January 18, 1926. Serial No. 81,886.

This invention relates to improvements in knitting machines, and more particularly to an automatic thread cutting attachment for such machines.

The main purpose of the invention is to provide a, thread cutting attachment of the character described which is subject to use on fiat stitch, purl stitch and other types of knitting machine and will operate in a reliable manner to automatically cut the separating or stripe threads as the case may be so as to prevent said threads from becoming entangled in the rolls of the machine and to prevent entanglement of the knit goods as sometimes takes place, due to the entanglement of said threads. At present it is necessary for the operator to cut or break thev stripe or separating threads by hand. If the operator fails to break thesethreads at the proper time, an entanglement of the threads and often the goods, will in most cases follow such neglect. On the entanglement of the thread or goods. or both, with the roller, a. shut down of the machinery is necessary and this results in a loss of time which proves wasteful and expensive in the operation of the machine. The present invention overcomes the above objections in that it automatically cuts the thread before the machine has operated to the extent that entanglement of the thread is likely and the operator is not required to devote time to the manual operation of cutting the thread.

lViththe above mentioned and other objects in view, the invention consists in the novel construction and combination of part-s hereinafter described, illustrated in the accompanying drawing, and set forth in the claims hereto appended, it being understood that various changes in the form, proportion, size and minor details of construction within the scope of the claims may be resorted to without departing from the spirit or sacrir ficing any of the advantages of the invention.

Referring to the drawing:

Fig. 1 represents a front elevation of the automatic thread cutter of my invention showing it applied to a knitting machine but part of which is shown.

Fig. 2 represents an end cutter as shown in Fig. 1.

Fig. 3 represents a top plan view of a detail of the invention.

elevation of the With the attachment of the invention, which may be either a separating thread or stripe thread. This thread runs through theknitted material A, along the line shown at C.

A separating thread provides for joining two pieces of knit material and for defining a-selvage on one of the pieces. The function of the stripe thread is obvious. In both instances these threads are intermittently and at spaced points run through theknitted material. If the threads are not cut or severed by hand, they will become entangled with the rollers 1, 2 and 3 in such manner that the material A will often also become entangled and a shut down of the machine is necessary to disentangle the thread and material.

The cutting attachment of my invention is mounted on the rod 4, being adjustable thereon. It comprises an upright standard 5 secured by means of an adjustable clamp 6 to the rod 4. On the upper end of this standard isa frame? for supporting a thread cutting means generally designated 8 and an auto-maticoperating means therefor general-v ly designated 9. Above the frame on an extension 10 thereof is a thread gripping device 11 which includes a spring jaw 12. The threadB passes through this gripping device and is held in proper relation to the other elements of. the knitting machine, not shown. after it is cut by the cutting means 8 which is disposed just below the gripping device 11.

The cutting means may be made up in various forms but in the present instance comprises a small pair of shears or scissors designated 13, one handle 14 of which is extended and pivotally connected as at 15 to a link 16'which is pivoted to a swinging armature 17. The armature 17 is adapted to be moved by means of electro-magnets 18 forming a part of the operating mechanism.

9. On energization of the magnets, the ted lines, the pressure of the thread on the armature moves towards-them and through the link 16 acts to move the blades of the scissors 13 together so as to cut the thread h B extending between the blades. The blades" are normally held open or apart by means of an expansion spring 19 mounted on a slide rod 20 pivoted to the handle 14 of the ;scissors and slidably mounted in the member 21 on the'frame 7.

.Anelectrical conductor 22 is connected with the magnets 18.and leads to a suitable electric socket 23 which socket is mounted on the lower end of the standard 5. On the 13 other side of the socket a conductor 24 leads I to a circuit'closer generally designated 25,

mounted on the frame 7 From this circuit closer a conductor 26 leads to the other side of the magnet 18. The plug 23 provides for connection of the electrical operatingdevice 2 the upper end of this arm is a lateral extension 30 having a V-shaped guide portion 31 in which the thread B 1s adapted to engage. Extending from the lower end of the. arm 27 is a short contact arm 32. The conductor 24 H is connected with the pivot 28 so that this contact arm 32 will close the circuit for the magnet when it is moved to engage a stationary' contact member 33 within the housing 29, the conductor 26( being connected with v the contact member 33. This circuit closing device may be modified as to its form as de; sired, the main requirement being that ,the

pressure of thethread B will act upon the circuit closing device so as to close the circuit and bring aboutan automatic operation of the cutter. 4 I Operation.

When a stripe or separation thread as indicated at Batter having been run through 2 the material A, moves downward with the material A, it will engage the lateral portion 30 of the trip arm 27 and the pressure of the thread B is placed upon the arm'27 such that on further downward movement of the material, the'pressure is increased. When the thread is moved into position shown in dotarin is such asto rock it and cause the contact portion 32 thereof to engage the contact member 33. This closes the clrcuit for the magnets and causes the armature 17 to swing ,teriaITA, it will engage between the plates as shown in Fig. 4'. The spring 10 retu rns the scissors and associated parts to normal position, the blades of the-scissors being open to rec'eive'the nex't thread. In this way the separatoror stripe thread is automatically severed beforeit is advanced in the machine to the extent that its entanglement with the threads in a knitting machine comprising a frame adapted to be mounted upon the knitting machine, cutting members one of which is movable relative to the other mountedon said frame and betweenfwhich the thread is adaptedto extend, an electro-magnet on the frame, a pivoted armature for the magnet, a link connection between the armature and said movable cutting member, an electrical circuit for said armature, a circuit closing devicein the circuit includin a movable contact member part of which is adapted to be engaged by the thread, said contact-member being arranged to move into contactmg position subject to predetermined pressure thereon by said thread. r

2. In combination with a knitting machine including rollers between which knitted goodsare advanced in the knitting operation, which knitting machinealso includes a separator or stripe thread joined with the knitted goods and disposed to one side of the latter and moved therewith on advancement 

